Reduction mill



March 12, 1940.

E. J. R. CHENOWETH v ,193,163

REDUCTION MILL Filed Aug. 26, 1937 3 Sheets-Sheet l INVENTOR EDWIN J, H.6HENOWETH March 1940- E. J. R; CHENOWETH 2,193,163

REDUCTION MILL Filed,Aug. 26, 1937 3 Sheets-Sheet 2 INVENTOR EDWIN J'. R. CHENOWETH I By ATTORNEYS March 12, 1940- E. J. R. CHENOWETH REDUCTION MILL Filed Aug. 26, 1937 3 Sheets-Sheet 3 INVENTOR EDWIN J. R. CHE-NOWETH .63 ,nym f H Patented Mar. 12, 1940 [UNITED STATES "PATENT OFFICE REDUCTION MILL Edwin J. R. Chenoweth, Renville, Minn. Application August 26, 1937, Serial No. 161,053,

2 Claims. (01. 83-93) of different sized screens, and a pair of grinding This invention relates to new and useful improvements in reduction mills and an object of the invention is to provide a simple and inexpensive apparatus of this character which is adapted for reducing cereals and other, commodities to one or more'degrees of fineness;

A further object of the invention is to provide a simple and inexpensive reduction mill for grinding rain and other materials, which is capable of classifying the ground material into different I grades, according to size, and also,

whereby the roughage or tailings is separated from the more useful material;

A further object is to provide an apparatus of the class described, comprising a revolving cylinder having a, plurality of suitable screens secured to the periphery thereof, which are of different size mesh, whereby the different size particles contained in a given mass of ground material may readily and quickly, be separated from oneanother by simply passing them through said cylinder. t

A further object is to provide a reduction mill comprising a suitable casing having a cylinder mounted for rotation therein, whose periphery is provided with a suitable cloth or screen fabric, divided into sections lengthwise of the cylinder and the mesh of said sections progressively varying in size lengthwise of the cylinder, whereby certainsize material will pass through the screen of each section, thereby grading and. classifying the ground material, in accordance tosize.

A further object is to provide a reduction mill of the typedisclosed comprising a rotating cylinder provided upon its surface with a plurality rolls being mounted within the cylinder and adapted to receive the material to be ground and classified from a suitable source, and whereby the operation of grinding the material and classifying it into a plurality of different grades, ac-

of similar capacity; and in the provision of such a machine whereby a portion of the material is continually being returned to the grinding rolls for regrinding, until all of the material delivered into the cylinder has been reduced in size, and classified into one or more grades, the

coarser and less valuable material, such as oat hulls, sticks, and other foreign matter, com monly known as tailings, being discharged from the machine at one end thereof.

Other objects of the invention will appear from the following. description and accompanying drawings and will be pointed out in the annexed claims.

In the accompanying drawings there has been disclosed a structure designed to carry out the various objects of the invention, but it is to be understood that the invention is not confined to the exact features shown as various changes may be made within the scope of the claims which follow. l

i In the drawings:

Figure 1 isa longitudinal sectional view on the line l-I of Figure 2, showing the general construction of the interior of the apparatus;

Figure 2 is a cross-sectional view substantially on the line 22 of Figure 1; and I Figure 3 is a sectional plan view substantially on the line 3-'--3 of .Figure 2.

The novel apparatus herein disclosed is shown comprising a suitablecasing, generally indicated by the numeral 2 and having perforated end walls 3 and 4, a top wall 5 and side walls 6 and 1.

A suitable cylinder, generally indicated by the numeral 8, is mounted for rotation within the casing 2, and comprises annular end members 9 and II secured together by suitable tie rods 12,

whereby they are retained in spaced relation, as

shown in Figures 1 and 3. The peripheries of the members 9 and H are preferably grooved, as

' shown at l3 in Figure l, and are supported upon" generally indicated by the numeral 22, and are geared together at one end of the apparatus by, suitable gears 23. The shaft extension at one end of the roll l9 isshown provided with a suitable pulley 20 for receiving a suitable drive belt.

The bearing boxes 22 of the roll l9 areshown provided with suitable adjusting devices 24, whereby the grinding contact of the two rolls may be varied, as is well known in structures of this general character. The bearing boxes 22 are shown supported upon the frame structure I I of the apparatus.

- tively coarse.

In the apparatus, as illustrated in the drawings, the cylinder 8 and rolls I8 and H! are shown divided into three sections A, B and C, whereby portions of the material may be subjected to three difierent grinding operations. It will also be noted, by reference to Figures 1 and 3, that the cylindrical wall of the cylinder 8 is composed of a suitable screen or cloth mesh, through which the material within the cylinder is sifted or passes during rotation of the cylinder. In the drawings, I have shown the cylinder provided with three different sizes of mesh. The

mesh 25 of section A is shown as being relatively coarse, andthe mesh or screen by sections B and C are shown relatively finer, whereby three different grades are obtained according to size. The number of sections in which the cylinder is divided may be varied, as desired, or all of the mesh of the cylindrical wall of the cylinder may be of the same size, whereby all of the material delivered into the cylinder for grinding will be reduced to the same degree offineness before being discharged therefrom. The relatively coarser material, such as sticks, and other foreign matter, commonly known as roughage, or tailings, is discharged from the end of the machine.

.As best shown in Figures 1 and 2, the sections A, B and C of the cylinder are provided with hoppers 23, 29 and 31! respectively, separated from one another by suitable partitions 32, end walls 33, and front and rear inclined walls 34 and 35, respectively. In the drawings I have shown the rear walls 34 of the hoppers supported on suitable brackets 30, and extending the full length of the cylinder. An independent front wall 35 is provided for each hopper, and these front walls are pivotally supported on suitable pivots 3% provided in the partitions 32 and end walls 33, whereby the lower edges thereof are adapted for swinging movement.

A feed roll 31 constitutes the bottom of the hoppers 23, 29 and 3| and is provided with suitable shaft extensions 38 supported in suitable bearing blocks 39. The bearing blocks are shown secured to suitable frames i i secured to the main frame 11 of the apparatus. The feed roll 37 is driven by a belt 42 from the shaft extension 2| of the grinding roll l9, as best illustrated in Figure l. The material to be ground and classified is delivered into hopper 28 of section A from a suitable supply spout 43. The feed rolls l8 and it are provided with annular peripheral grooves 40, adapted to receive the lower edges of suitable separators 50, which confine the material discharging from the hoppers to the portions of' the grinding rolls aligned with the respective hoppers.

Afeature of the invention resides in the novel construction of the cylinder whereby portions of the partiallyground material are constantly being returned to the rolls I8 and IQ for regrinding. The grinding rolls l8 and iii are preferably disposed at a slight angle with respect to each other, whereby the peripheries thereof are spaced slightly farther apart at the receiving end of the machine than at the opposite end thereof, whereby the material passing between the feed rolls in section A of the cylinder is ground rela- The ground material discharging from the feed rolls in section A is precipitated into an inclined trough :26, which diverts the material to the extreme left-hand end of the cylinder when viewed as shown in Figure 1, whereby as thecylinder rotates, the material whichhas been reduced to a degree of fineness whereby it may pass through the perforations of the screen or cloth mesh 25 of section A, will be discharged into a suitable receiving means, such as a conveyer 45, which delivers the ground material to a suitable receiving means, not shown.

The material which is too coarse to pass through the perforations of screen 25 of section A, is elevated by a plurality of blades 46, provided Within the cylinder, to aninclined trough 41 disposed over the-hopper 29 of section B. The material thus elevated by the blades 48 and delivered into trough 41 is subjected to a second grinding operation, as it must again pass between the grinding rolls which, at this point, are spaced relatively closer together so that the material passing through the grinding rolls in section B, will be ground relatively finer than the material passing through the rolls in section A.

The material discharging from the grindingrolls in section B is delivered into a trough 48, which diverts it in a direction towards the receiving end of the apparatus, as clearly illustrated in Figure 1. Suitable partitions 49 and 5| are provided between sections A and B, and B and C, respectively, to confine theground material in the lower portionof their respective sections, as clearly illustrated in Figure l. The material in the bottom of section B, which does not pass through'the screen 26, is elevated by blades 52 and deposited into a trough or spout 53, which delivers it to the feed rolls within section C. The feed rolls l8 and H], because of being disposed at a slight angle with respect to one another, have their peripheries spaced relatively close together in section C, whereby the material passing therebetween is reduced to very fine particles, substantially in the form of fiour, which material is delivered onto an inclined trough 54, which diverts it towards the partition 5! defining oneend of section C.

The relatively coarser material, such as straw, sticks and the like, commonly known as roughage or tailings, is elevated from the bottom of chamber C and deposited into a spent 55 by blades 56 provided in section C of the cylinder. The roughage or tailings is discharged into a spout Bl which conveys it to a suitable receiving means, not shown. Thefinished material or produce passing through the screens 26 and ti of sections B and C, may be discharged upon conveyers 58 and 59, respectively, for delivery into suitable receiving means, not shown.

The novel apparatus herein disclosed, is comparatively simple in construction and provides a very compact unit, requiring very little floor space, as compared to conventional machines for grinding material, and where the material is subjected torepeated grinding operations. In the operation of the machine herein disclosed, the material to be ground or reduced in size is delivered into the hopper 23 of section A from spout t3, and is fed between the grinding rolls l8 and I9 by the feed roll 3?. The hinged walls 35' of the hoppers control the delivery of the material to the grinding rolls, as will be clearlysimilar grinding operation takes place, until all of the material delivered into the apparatus from the spout 43 has been reduced to a plurality of different grades according to size. The tailings, as previously stated, is delivered into the chute 55 anddischarged into the take-ofi spout 51.

In the present application, I have shown a structure wherein a portion of the material is subjected to two or more grinding operations. It is to be understood that, if desired, additional sections may be added, if necessary, in order to reduce the material to the desired degree of fineness.

It will also be noted that in Figures 1 and 3, the screens providing the peripheral wail of the cylinder 8 is provided with different sized perforations or openings in sections A, B and C, whereby three different grades of the material, according to size, are obtained. It is to be understood that in some cases, the screen or gauze forming the peripheral wall of the cylinder 3, may be of the same size mesh the entire length of the cylinder, whereby all of the material delivered into the apparatus will be reduced to the same degree of fineness before it is discharged from the cylinder, with the exception of the roughage, which is discharged from the machine into the spout 5?, as hereinbefore stated. Portions of the material, however, will repeatedly be returned to thegrinding rolls for regrinding until all of the material has been reduced to, a given size.

In Figures 1 and 2, I have shown the cylinder 8 provided at one end with an annular member 60 having a peripheral groove 6i adapted to receive a belt 62, operatively engaged with a pulley 63 secured to the shaft of a suitable motor 64-. This motor rotates the cylinder 8 independently' of the grinding rolls l8 and i9 and feed roll 37.

I claim as my invention:

1. In a machine of, the class described, a cylinder mounted for rotary movement and divided into a plurality of sections, lengthwise of the cylinder, the walls of the cylinder being uniformly perforated the length thereof, whereby the perforations in the walls of all of said sections are uniform in size, grinding means within said sections, means for delivering material into the grinding means in a section at one end of the cylinder, a lower trough disposed beneath the grinding means in each section adapted to return the ground material to the receiving end of each' section, each section having an upper trough disposed above its complemental grinding means, conveyer means in each section adapted to convey portions of the material from the bottoms of said sections, and deliver it into said upper troughs, said upper troughs operating to convey the material from the conveyer means of one section to the grinding means of an adjacent section, and said conveyer means and upper troughs cooperating to return portions of the material to the grinding means and progressively advance it from one section to another until substantially all of the material has been reduced to a predetermined size.

2. In a machine of the class described, 2. cylinder mounted for rotary movement and having a perforated wall, the interior of said cylinder being divided into a plurality of sections, grinding means within said sections, means for delivering material intothe grinding means in a section at one end of the cylinder, a lower trough disposed beneath the grinding means in each section adapted to return the ground material to the receiving end of each section, each section having an upper trough disposed above its complemental grinding means, conveyer means in each section adapted to convey portions of the material from the bottoms of said sections, and deliver it into said upper troughs, said upper troughs operating to convey the material from the conveyer means of one section to the grinding means of an adjacent section, and said conveyer means and upper troughs cooperating to return portions of the material to the grinding means and progressively advance it from one seetion to another to reduce the material in size,

the perforations in the cylindrical walls of said sections being of different sizes, whereby the material delivered into the receiving end of the cylinder is reduced to a plurality of different sizes, as it is progressively passed through said sections.

EDWIN J. R. CHENOWETH. 

